Systems, apparatuses, and methods consistent with exemplary embodiments relate to an electronic system and an image processing method, and more particularly, to an electronic system including an image signal processing device compensating a white balance of an image and an image processing method thereof.
As a digital technology develops, a digital camera capable of shooting an image without a film is being rapidly developed.
The core of a digital camera may include an image sensor unit that captures an image, or an image processing unit that processes a digital signal. Due to a difference in image quality and a color of a digital camera and those of a film camera, a study and an improvement in an image processing field of the digital camera are needed. In particular, a color processing for a natural color reproduction is the core in an image processing field.
When shooting the same subject using a digital image device such as a digital still camera, a digital video camera, etc., an apparent color shot becomes different depending on various light source conditions such as a solar light, cloudy weather, white lightning, fluorescent lightning, etc. Since a human eye adapts itself to a light source to feel white as white, the human eye does not feel unnaturalness. However, in a digital image device, color temperature sufficiently responds to KGB components included in different light sources. If the color temperature is high, the color is reproduced as white tinged with blue. If the color temperature is low, the color is reproduced as white tinged with red.
Thus, even in the case that color temperature is changed, it is desirable to maintain a white balance. To achieve this, it is controlled such that in an achromatic color subject, an RGB ratio is always constant or color difference signals R-Y, B-Y become always substantially zero. Performance of that function is called a white balance correction. That is, in white tinged with blue, gain of R (red) is increased more than gain of B (blue), and in white tinged with red, gain of B (blue) is increased more than gain of R (red).